San Diego  A Mexican millionaire’s defense that Sempra Energy and negligent investigators are to blame for his current charges in a campaign financing scheme lost some steam Monday, with a San Diego federal judge calling his requests for certain evidence irrelevant, overbroad and vague.

José Susumo Azano Matsura — a part-time Coronado resident accused of secretly funneling some $600,000 in illegal donations to the campaigns of former San Diego Mayor Bob Filner, District Attorney Bonnie Dumanis, and congressman Juan Vargas — had asked prosecutors for volumes of additional material in hopes of uncovering a flawed investigation.

In court papers late last month, Azano's lawyer said aggressive investigators have been after Azano for years on unsubstantiated and “wild” allegations of criminal activity, from drug smuggling to arms trafficking. He said these so-called “rogue” investigators pounced again when Azano got involved helping pay for an Ensenada landowner’s fight with Sempra over a gas plant.

Those same investigators, working on behalf of Sempra, are now coming after Azano in the campaign finance case, claimed Azano’s lawyer, Knut Johnson.

Assistant U.S. Attorney William Cole argued that the smoking gun just isn’t there. “We don’t know what they’re looking for, other than things we don’t believe exist,” Cole said.

U.S. District Judge Michael Anello largely denied the request for evidence relating to Sempra as “irrelevant” and “immaterial” to the case.

Azano’s lawyer also complained that prosecutors caused irreparable damage to Azano’s reputation when they detailed in court papers the many times he popped up in connection with a wide range of criminal investigations, including drug smuggling, tax evasion and illegal immigration. Azano was never arrested or charged in those probes.

“It’s almost laughable for the government to try to connect Mr. Azano to 69 pounds of marijuana at the border,” Johnson said, referring to the government’s mention of an investigation that allegedly traced a load car to the address of Azano’s then-wife in 1996. He said the significant publicity may prompt him to ask for a change of venue to find impartial jurors.

Cole told the judge that prosecutors had no intention of revealing the other investigations at this point, but felt they were forced to respond after getting “hit over the head” with Azano’s allegations of investigative misconduct. “We feel it was a fair response,” Cole said.

The judge agreed that the publicized information may have negative repercussions for Azano and, at the prosecutor’s suggestion, ordered that section of the court document be sealed.

Azano’s lawyer was less successful at getting at the reason why U.S. Attorney Laura Duffy, the top federal prosecutor in the region, recused herself from the case. Her office has said Duffy didn’t believe a conflict of interest existed, but recused herself at the outset to avoid the appearance of one.

Prosecutors stated last week that the reason for her recusal does not matter in this case, and speculation as to why is “a road leading to nowhere.” Johnson countered in a motion that the reason does matter and could taint his client’s right to a fair trial. “How is the rest of her office … not subject to the same conflict?” he asked.